DIN SPEC 1097
DIN SPEC 1097 Welding - Grouping systems for materials - European materials (ISO/TR 20172:2009); German version CEN ISO/TR 20172:2009
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 10/01/2009
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 10/01/2009